1. Technical Field
The present invention relates to discharge systems for discharging gases produced in die-casting machines to the outside of the die-cast machines. The present invention also relates to methods for discharging gases from the die-cast machines.
2. Description of the Related Art
In general, die-cast machines are equipped with spray devices that serve to spray mold-releasing agents onto a mold after a cast product has been removed from the mold. The die-casting machines also are equipped with discharge systems that serve to discharge the mold-releasing agents that have been gasified after sprayed onto the mold. Japanese Laid-Open Patent Publication No. 6-126416 teaches a known discharge system for discharging a gasified mold-releasing agent as an exhaust gas. The known discharge system includes a hood for covering the upper portion of a mold and also includes a discharge duct that is connected to the hood. A blower is mounted on the discharge duct and is operated to draw the gasified mold-releasing agent upward with respect to the mold.
However, in the known discharge system, the hood covers only the upper side of the mold. Therefore, even if the suction force produced by the blower is increased, only a limited portion of the gasified mold-releasing agent can be prevented from dispersing to the outside of the mold. Therefore, a portion of the gasified mold-releasing agent may be dispersed to the outside, thereby disadvantageously affecting the working environment.
Therefore, it is one object of the present teachings to provide improved techniques for reliably discharging gases that may be produced in die-casting machines.
In one of the aspect of the present teachings, discharge systems may discharge gases produced in die-casting machines. The die-casting machines may include a first die and a second die arranged and constructed to form cast products. A cavity may be defined between the first die and the second die. Molten material may be injected into the cavity, so that products may be cast to have a configuration that conforms to the configuration of the cavity.
Preferably, the discharge systems may include a closure device and a transfer device. The closure device may define a substantially enclosed region between opposing surfaces of the first and second dies.
In another aspect of the present teachings, the fist and second dies may define a part of the enclosed region when they are opend. In other words, the first and second dies may serve as a part of the discharge system. The remaining portions of the closure device may be defined by shield plates or air curtains that may be formed by streams of air. In this specification, the term xe2x80x9csubstantially enclosed regionxe2x80x9d is intended to include a region that is completely sealed to inhibit the flow of fluid to and from the region, or a region that is not completely sealed from the outside, but is surrounded and shielded by the closure device such that fluid in the region may be substantially prevented from dispersing to the outside of the region or entering the region.
In another aspect of the present teachings, a transfer device may transfer the gases within the enclosed region to the outside. Preferably, the transfer device may include a blower for charging or forcing air into the enclosed region, a suction blower for drawing the gases from the enclosed region, or a combination of these blowers.
Therefore, gases produced within the die-casting machines may be confined within the enclosed region, so that unfavorable dispersion of the gases to the outside of the enclosed region may be minimized. The gases within the enclosed region may be discharged to the outside by means of the transfer device. As a result, the working environment surrounding the die-casting machines can be maintained in a favorable condition.
Thus, the dispersion of the gases to the outside of the enclosed region may be reliably prevented and the gases may be reliably discharged to the outside. In particular, these discharge systems may be rationally configured, because the first and second dies of the die-cast machines can be utilized as a part of the closure device.
In this specification, the term xe2x80x9cgasesxe2x80x9d may broadly include vapors, mists or mixtures of vapor and mist. For example, gases that may be produced in die-casting machines may include mold-releasing agents that have been gasified after application to the mold. The mold-releasing agents are generally used to ensure the removal of the cast products from the mold. Furthermore, the gases may include cooling water that has been sprayed onto the mold and vaporized after cooling the mold.
According to another aspect of the present teachings, methods for discharging gases produced in die-casting machines are taught. The methods may optionally include a step of defining a substantially enclosed region between opposing surfaces of the first and second dies by the first and second dies. Further, the methods may include discharging gases within the enclosed region to the outside.
Additional objects, features and advantages of the present invention will be readily understood after reading the following detailed description together with the accompanying drawings and the claims.